Pipe cutter



Filed April 8, 1937 Guy P Ellis James 'I Ellis INVENTORJ BYl W/ u lgl.l

Patented June 4, 1940 UNITED STATES PATENT OFFICE 5 Claims.

'I'his invention relates in general to a pipe cutter, and more specifically has reference to a pipe cutter of that type designed to move into the interior of a drill pipe and to cut the same from 5 Within at a predetermined point.

In the drilling of oil Wells and the like it is not an infrequent occurrence for casing or a drill stem to become stuck in a well hole in such a manner that it becomes impossible for it to be l removed in the ordinary manner lby pulling upwardly thereon. In such instances, it becomes necessary to lower into the well a pipe cutter having blades which may be expanded'in a radial direction and a means by which the cutter may be 1 moved to sever the pipe which has been stuck, and pull it out piece by piece. Numerous pipe cutters have been designed for the purpose set forth, the blades of such cutters being operated principally either by manipulation of the tubing by which the cutters are constantly suspended, or by means of energy in theform of fluid pressure or electrical energy transmitted from the surface ofthe hole. l

It is an object of this invention to provide a cutter of the type set forth in which the cutter may be rmly and positively anchored prior to the expansion of the cutter blades.

It is a further object to provide such a cutter with a positive means for releasing the cutter from its anchorage.

Another object is to provide a pipe cutter in which blades of the cutters will have the maximum amount of radial movement for a minimum amount of longitudinal movement with respect kto the pipe to be cut.

Another object of this invention is toprovide a pipe cutter ofthe type set forth in which it will be impossible for the blades to be expanded until the cutter has been firmly anchored within the p1pe.

Another object is to provide a pipe cutter of the type set forth with a means for positively and releasably preventing the actuation ofthe anvchoring means.

Another object of this invention is to provide in a cutter of the type set forth a latching means which will prevent the actuation of the anchoring means, and which will be rotatable with respect to the anchoring means during the operation of the cutter. l y

One other object of this invention is to provide a pipe cutter which will pass through the reduced bores of the tool Ajoints of a drill stem, and which may be anchored within a drillstem for thepurg" pose: of severinga portion' of the same.

Another object of this invention is to provide a pipe cutter of such a diameter that it will pass through the reduced portion of the tool joint of the drill stem and which may be anchored within the drill stem in such a manner as to sever the drill stern at a point where the Wall `thereof is thinnest.

Other objects and advantages of this invention will become apparent from the. following de-` scription taken in connection with the accom; panying drawing, both of which are by Way of illustration only. It is to be understood that this invention is to be limited only by the prior art and by the terms of the appended claims.

In the drawing: n

Fig. 1 is a view taken in vertical cross section illustrating a pipe cutter constructed in accordance with this invention in place within a pipe which is to be cut thereby.

Fig. 2 is a View partly in vertical cross section illustrating in elevation a portion of the device shown in Fig. 1.

Fig. 3 is `a view similar to a portion of Fig. 1 but I illustrating the parts with the blades in their cutting position, and the anchoring means anchored within the internally upset end or joint portion of an internally upset section of drill pipe.

Fig. 4 is a horizontal cross section taken along the line 4 4 of Fig. 1.

In Fig. 1 there is illustrated a pipe l which is adapted to be severed by the cutter shown. This cutter is suspended upon a pipe or tubing 2 having a special shaft'3 secured thereto at its lower end. Intermediate its ends the special shaft A3 is provided with laterally extending lugs 4 for a purpose to be presently set forth, and at its lower end is provided with a female thread at 5 to receive the upper end of a second special shaft 6. To the lower end of this special shaft 6 there is secured an end mill member 1 which .serves as a guide for the device as it is being lowered into the well and with which a collapsed orconstricted portion of the pipe may be opened up. y

Intermediate its ends, the special shaft 6 is provided with milled out portions, 9 having sub-- stantially parallel surfaces intermediate their ends, and having outwardly tapered or flared place within the shaft by means of pins I2 or the like. These keys extend beyond the shaft on each side thereof and lie in substantially the same plane. Their corners adjacent the milled out portions 9 are beveled so as to form substantial extensions of the beveled end surfaces Ill of said milled out portions. This is illustrated at I3 in the drawing and clearly appears in Figs. 1 and 3.

Surrounding this portion of the shaft l and slidably mounted on the shaft is a sleeve I4 having longitudinal slots I5 therein so limited as to slidably receive the protruding ends of the keys II. Cutter blades I6 mounted on cutter arms I7 are carred by this sleeve within the said slots, these arms being pivotally mounted upon pins I8 extending across the slots as clearly illustrated in Fig. l. These cutter arms I'I are of such length that their opposite ends will be in constant `contact with the flared end surfaces II! of the milled out sections of the shaft and lwith the extensions of these surfaces asformed by the beveled edges of the keys I I. It will be seen that as the shaft 6 is moved upwardly with respect to the sleeve I4, the surfaces I0 and I3 previously referred to will operate as cams to cause the cutter arms I'I to pivot about their axes ,I8 and to move the cutter blades I6 into contact with the inner surface of the pipe I within which the cutter is positioned. The sleeve I4, however, is normally held in its upper position with respect to the shaft Bas illustrated in Fig. 1 by means of a spring I9 bearing at its lower end against the upper surface of the end mill 'I and at its upper end against the lower end of the sleeve I4.

Located at the upper end of the sleeve I 4 is an externally tapered expansion ring 20 adapted to contact with the inner surface of and expand a set of slip segments 2l into contact with the inner surface of the passage 22 through the upset end of the section of drill pipe. It is to be understood that while the cutter is shown as being anchored within the upset end portion of a section of pipe, it may be anchored at any point within the reduced passageway in or acljacent the tool joint. The ring 2l) is freely slidable upon the shaft 6 and the slip segments 2l are formed integral with a ring-like portion 23 from which they are suspended. The upper end of this ring-like portion 23 is threaded to receive a fitting 24 forming one race of a set of ball bearings 25. The other race for this set of ball bearings is formed by a fitting 26 which is in turn threaded to the lower end of a sleeve 21. The sleeve 2l is thus rotatably-con.- nected to the ring 23 with which the slip segments 2l are integral and from which they are suspended.

The sleeve 21 is provided in its opposite faces with slots 28 of J formation as illustrated in Fig. 2, the laterally extending portion ofthe `J being at the lower .ends of these slots. The lugs 4 which were previously referred to are of such a size and in such a position as to move within these J slots, and it is contemplated that they terior surface of the expanding ring 20 which rests on top of the sleeve I4.

Duri-ng this lowering of the cutting tool, if

a collapsed portion of the drill steml should be encountered, or if it should be found to be plugged by some foreign substance, a rotation of the suspending string 2 will cause the end mill l to mill through and remove the obstruction, thus openk ing the path for the tool to be lowered into the drill stem. During this rotation, the lugs 4 will not be disengaged from their J slots'beoause such rotation will tend only to more firmly en gage these lugs in` the lower `ends of these slots.

It is to be understood that the slip segments are so formed that in their passage downwardly through the drill stem and during the time they are being held out of engagement with the expanding ring 2U, they will not contact the in- .f

terior of the drill pipe proper except at the internally upset portions thereof and within the tool joints themselves. duced diameter, however, the slip segments ZI will contact with the inner surface of the bore,

tion that the slip segments 2l are positioned' within a section of the drill stem 4of reduced diameter such as within the tool joint itself or within the upset end portion of a .sectionof drill pipe.

The string 2 by which the cutting tool is suspended will then be rotated to the left slightly to disengage the lugs 4 from the lower laterally extending portionsof the J `slots 28; Thereupon, the string v2 will be moved upwardly and since the sleeve 2l is no longerlatched against longitudinal movement with respect to the lshaft 3, the slip will remain in position and the ex` panding ring 20 will be moved upwardly into engagement therewith. Acting through the spring I9 and the sleeve I4 further upward move- At these portions of rement of the string 2 will wedge lthe expanding ring 20 tightly within ,the slip segments so as'to anchor the cutting tool with the cutter blades I6 positioned a substantial distance below the restricted or tool joint portionof the drill stem.

After` the slips are firmly set, further upward movement lof the string 2 will compress the spring I9 and cause the shaft 6 to move upwardly with respect to the sleeve I 4. This movement, yas hereinbefore pointed out, will cause the cutter arms I'I to be rotated about their pivotal supports I8 until they occupy a position somewhatr as shown in Fig. `3. During this time, the spring I9 is being compressed so' that a constant upward pull must be exerted upon the string 2 in excess of its weight to holdthe cutter blades against the` inner surface of the pipe to be cut. The string 2 is then rotated to vcause the cutter blades to cut the inner surface of the pipe and as the cutting proceeds the, string 2 will be gradually drawn upwardly until the pipe is'completely severed. It is to be noted that during this operation the position of the cutter' arms and hence of the blades I6 may be accurately and positively controlled by virtue of the factthat bothv ends of the cutter arms are in contact with actuated cam surfaces at all times. Thus, it is possible tov positively prevent the cutters I6 yfrom hogging the out and becoming stalled or broken.

, It is further tobe noted that during'this expending movement of the cutting bladesv I6 the blades and arms on which they are mounted do not move either` upwardly or downwardly. Instead, they are anchored positively against upward longitudinal movement with respect to the pipe being cut, Aand are constantly urged up'- wardly so that they' have no downwardl movement with respect to such pipe.

During the' rotation of the string 2 for Athe purpose of cutting the pipe, the `keys' II projecting as they do from the lateral surfacesof the shaft 6 into the slots I5 in the sleeve I4, will directly cause the rotation of' this4 sleeve, thus positively driving the cutter blades. in their rotational movement.

The lugs. 4 remain at all times within the J slots in which they operate, and the sleeve 21 in which such slots are'formed is freely rotatable with respect to the slips and the ring 23 from which they are suspended. There isthus no problem of guiding lthe lugs 4 back into the J slots.

After the pipe within which the cutter has been anchored is severed as previously described,

the string 2, together with the shafts 3 and 6, will then be lowered. During the initial part of this lowering operation the spring I9 will expand so that the shaft 6 will move downwardly with respect to the sleeve I4 and retract the cutter blades before they are moved longitudinally with respect to the pipe. Further downward movement of the shaft 6 will permit the sleeve I4 to move away from the expanding ring 20 luntil the lower end of the shaft 3 which is of slightly larger diameter than the shaft 6 strikes the upper end of the expanding ring 20. This will move the expanding ring from its position Within the slips and permit the shafts 3 and 6 to move downwardly still further with respect to the slips. The lugs 4 upon reaching the lower ends of the J slots may by right hand rotation of the string 2 be caused to engage the lateral portions of the J slots and upon upward movement of the string 2 the sleeve 21 and the slips 2I will be moved with the string. Another location for cutting may then be selected and another cut made, or the cutter may be removed from the hole, as desired. lIt is noteworthy that after the pipe has been severed, the cutter may be' moved either upwardly or downwardly in the same manner as before the pipe was severed.

From the foregoing it willbe seen that there has been provided a pipe cutter which may be lowered through the portions of restricted diameter of a drill stem, and which may be anchored within the drill stem in such a manner as to sever the same at a position where the walls of the drill pipe vare thinnest. Means has been provided whereby this cutting device may be operated easily and rapidly while being positively controlled at all times. It may be made of suiiiciently small diameter to pass through the restricted portions of the drill stem, and because it is adapted to anchor within such restricted portions, it is unnecessary that the anchoring means be greatly expanded during the anchoring operation.

While one embodiment of this invention has been set forth by way of example, it is to be understood that various changes and modifications may be made therein without departing means for anchoring said cutter supportngainst upwardmovement in a pipeto be cut, expansible cutters mounted insaid cutter support, an` actuator membermovable longitudinally with respect tovsaid cutter support to cause 'expansion and contraction of said cutter blades, means slidably interconnecting said actuator and said cutter support whereby rotation of said actuator Will cause rotation vof said cutter support and said cutter, means on said actuator for releasably securing said anchoring means in inactive position, and means for normally urging said actuator in the direction with respect to said cutter support such as to cause contraction of said blades.

y2. In combination, in a cutting device for sevcring a pipe having parts o-f larger and other parts of smaller inner diameter an anchoring means adapted to pass freely through the portions of such pipe of larger inner diameter, and to resiently engage the portions of such pipe of smaller internal diameter, an actuator for extending through such pipe and having parts thereon forming a latching device and detachably maintaining said anchoring means in inactive position, a cutter support resiliently supported upon said actuator, means ycarried by and rotatable with respect to said cutter support for actuating said anchoring means upon upward movement with respect thereto, cutter blades on said cutter support, and means on said actuator operable upon upward movement of said actuator with respect to said cutter support to expand said blades and upon rotative movement of said actuator to rotate said cutter support and said blades.

3. In combination, in a means for severing a pipe having internally upset portions, a shaft adapted to extend into such pipe, a cutter-carrying sleeve resiliently, slidably and non-rotatably supported upon said shaft, an upwardly tapered wedge ring freely movable upon said shaft and rotatably supported on said cutter-carrying sleeve, an expansible anchoring means slidabley and rotatable with respect to said shaft above said ring and adapted upon upward movement of said shaft with respect to said anchoring means to be expanded by said ring into anchoring position Within such pipe, said anchoring means when not expanded being of a size to pass freely through the portions of said drill stem of larger diameter and to frictionally engage the internally upset portions, a sleeve for rotatably supporting said anchoring means out of contact with said ring, an anti-friction bearing rotatably connecting said sleeve and said anchoring means, a closed J slot connection between said sleeve and said shaft whereby said sleeve may be latched in an upper position with respect to said shaft to support said anchoring means out of contact with said ring, expansible cutter blades carried by said cutter-carrying sleeve, means on said shaft adapted upon upward movement of said shaft with respect to said cutter-carrying sleeve to expand the cutters thereon into cutting engagement with such pipe, and on downward movement of said shaft with respect to said cutter-carrying sleeve to retract the cutters from such cutting engagement, means for resiliently urging said shaft downwardly with respect to said cutter-carrying sleeve, and means on said shaft to force said wedge ring out of expanding contact with said anchoring means upon further downward movement of said shaft after said blades have been retracted.`

4. In combination, means for severing a pipe comprising a shaft adapted to extend into such pipe,a cutter-carrying sleeve resiliently, slidably and non-rotatably supported upon said shaft, an upwardly tapered wedge ring freely movable upon said shaft and rotatably supported on said cutter-carrying sleeve, an expansble anchoring means slidable and rotatable with respect to said shaft above said ring and adapted upon upward movement of said shaft with respect to said anchoring means to be expanded by said ring into anchoring position Within such pipe, supporting means for rotatably supporting said anchoring means out of contact with said ring, anl antifriction bearing rotatably connecting said supporting means and said anchoring means, a closed J slot connection between said supporting means and said shaft whereby said supporting means may be latched in an upper position with respect to said shaft to support said anchoring means out of contact with said ring, expansible cutter blades carried by said cutter-carrying sleeve, and means on said shaft adapted upon upward movement of said shaft with respect to said cutter-carrying sleeve to expand the cutters thereon into cutting engagement with such pipe.

5. In a means for severing a pipe, a shaft adapted to extend into said pipe, a cutter-carrier resiliently, slidably and non-rotatably supported upon said shaft, an upwardly tapered wedge member freely movable upon said shaft and rotatably supported on said cutter-carrier, an expansible'anchoring means slidable and rotatable with respect to said shaft above said member and adapted upon upward A.movement of said shaft with respect to said anchoring means to be expanded by said member into anchoring'position within said pipe, supporting means for rotatably supporting said anchoring means outof contactvwith said ring, abearing rotatably connecting said supporting means and said anchoring means, a releasable connection between said supporting means and said shaft whereby said supporting means may be latched in an upper position with respect to said shaft to support said anchoring means out of contact with said Wedge member, expansible cutter blades carried by said cutter-carrier, and means on said shaft adapted upon upward movement of said shaft with respect to said cutter-carrier to expand the cutters thereon into cutting engagement with said pipe.

GUY 15. ELLIS.

JAMES T. ELLIS. ,y 

